Container Soils - Water Movement and Retention III

I so glad I stopped in, cause I filled the RB Saturday, and forgot to mix in the EP and Dolomite Lime....and, I bought a 40 lb. bag of Triple 13 yesterday.

Bringing it back today, and going with my MG water soluble...24-8-16....

Thanks, Al!

BTW, do you know how heavy 1/4 yard of sharp sand is?

H - E - A - V - Y !!!!

YP, Linda

I haven't been around the forums much this last week. Our weather went from regular MI winter weather to two weeks of really warm weather, including the last week in the upper 70s and 80s. I have well over 100 deciduous bonsai to repot, and they're ALL showing significant bud movement, so I took the week off. I've been working 12-15 hours repotting every day since Fri, trying to keep ahead of the trees. The forecast is for at least another week of unseasonably warm temps, too!

Good luck with your project, L. TTYL.

YPA

Pine bark is appropriate because it's rich in a lipid called suberin, which is nature's waterproofing for plants. Most hardwood bark lacks the amount of suberin found in conifer bark. As a result, it breaks down much faster. This makes soils made from hardwood bark less structurally stable and makes nitrogen immobilization (tie-up) a significant issue. Because of the rapid decomposition, heat-build up is also a frequent issue when using materials that break down quickly (think 'hot compost pile'). Finally, there is usually a high pH spike associated with the use of hardwood bark/sapwood/heartwood at some stage of the composting process that causes many of the micronutrients to precipitate and become unavailable.

For the gritty mix, uncomposted pine or fir bark is ideal. For the 5:1:1 mix, either partially (that's slightly) composted pine bark or uncomposted bark are suitable with the slightly composted getting the nod. What you see at 3, 6, and 9 in the picture below are all good for the 5:1:1 mix.

Al

Thanks, Al, that makes a lot of sense, I will stick with the composted pine bark. Does that price seem reasonable? I can't find anything else like it around my area. I am a "club" member, so I'll get a 10% discount, but still, the price jumped 30% since last year, and I had sticker shock when I went in the shop. I will be needing a number of bags for my tomatoes.

I wish your photo had a size reference, like a dime or something. Sorry, I don't eat Sugar Pops (never did!) ;) Are they the same size as Kix? ;) ;)

I went to English Gardens today and found "100% organic pine bark mulch" and compared it to the composted pine bark. I decided on the mulch because I think the other was more than just "slightly composted". And even better, after volume purchase of 4 bags and member discount, it came to about $3.75 a bag! That means your recipe will cost me much less than buying the Miracle Gro potting soil I've been using for years! Woot!

Made another batch today, and the new mulch is much more "fluffy" than the batch I made the other day. And it smells great!!

BTW, Al what do you do with last year's material?

Last years material goes into the compost pile or gets added to raised beds as mulch.

Al

I tried $3.50 bags from Home Depot, and $7.50 bags from a classy nursery. The fnacier bag called itself "medium pine bark mulch" and the HD bag had a much vaguer name.

The more expensive bag seemed to have been double-screned, and had much less bark powder. More annying to me, the HD bag was soggy, smelled a little fermented, and had dirt, sticks and huge bark chunks.

I guess "dirt" and "composted" matter less for an RB, but I was making a coarse seed-starting mix ... not many people reccomend bark for starting seeds!

I've browsed through the posts about your mix for the container usage and was wondering about a formula that I was contemplating to use.

The MG Potting Mix,3 bags@ 64 quart size, 1 bale 3L compressed peat moss, and 2 bags composted manure. I was thinking the manure compost would help add nutrients to the mix. I plan on using this for 5 gallon tomato containers, and also some larger tote type containers for okra, cukes, and going to try lettuce in a container.

This is my first shot at doing containers and need some help...

PS.. Is there any difference between the MG regular Potting Mix & the Moisture Control??

The moisture control has water-retaining crystals that might cause your mix to hold too much moisture...

Add some perlite to your mix.

Everything you propose to use in your mix is fine particulates, so you can be sure your soil is going to be VERY water-retentive, so I think you're probably going to be significantly limited by too much water and too little air in the soil.

There is nothing in the manure you can't get from a fertilizer, and if you choose the right fertilizer ratio, you can pretty much have complete control over your plant's nutrition. You have no way of knowing what is in the manure or when it will be available as a nutrient for uptake because it has to break down first. That means that you'll have to fertilize, and since you have no idea what's in the manure, you're going to be duplicating a lot of nutrients unnecessarily, or growing under deficiency conditions if you don't fertilize. From this, you can see the manure has more potential to be limiting than to be a plus.

If you read the OP carefully, you'll see the emphasis is on soil structure, particularly on its ability to provide enough air in the root zone. If you keep this as your focus when you decide to go about making your soil, you won't go wrong. In order to do that, you'll need to be thinking about a very large fraction of your soil being larger particles - like pine bark.

If you embrace the concept put forth in the OP, you'll significantly increase your margin for error and increase the likelihood your plants will have the opportunity to grow much closer to their genetic potential. You'll need to invest some time, but I promise if you gain an understanding of how to manage the air:water relationship in your soils, it will be an asset that will help you in ALL your container gardening endeavors. It's literally the difference between building a soil that works for you or against you.

Al

Kevcarr, your recipe sounds almost exactly like what I had been using for the past several years for my tomatoes in containers...and last year for peppers. I've had lackluster results with the tomatoes, and came here looking for some ideas on how to improve my harvest.

After reading Al's advice, I decided to try his recipe this year. Once he mentioned about the compaction and lack of air at the roots, I knew exactly what he meant. When I pulled my peppers out of the pots, I had all kinds of roots except in the bottom two inches or so, where it was obvious they couldn't grow because of the perched water.

I don't have any experience to share yet, but after mixing up several batches, I can attest that it is much "fluffier" and I can see that it will keep more air in the root zone. I grow orchids, too, so I get the idea that roots need air...I just never translated that to my container plants!

I've got lettuce growing in the "fluffy" now...they look pretty good, although it's only been a couple weeks. Tomatoes will be going in sometime in May.

Since you're just starting out, it might be fun to experiment and do one container with your mix, and one with Al's, and compare your results.

Al, any chance we backwoods dialuppers could get a new thread? Thanks!

koshki>> As I said before, this is my first foray into container gardening, and since you have had so-so results, with a similar formula, I think I'm going to pass on mine, and give Al's a shot. It seems many people are using it, and getting good results with it. I guess my biggest problem is finding some of the components locally, besides going to the big box stores. We have a Gardenville (run by Texas Disposal Systems) store just down the highway from us and that is where we get our bulk garden soil & mulch. They don't have a pine bark mulch on their price list, so I may have to find another source for that component in the formula.

Al>> Is there any difference between perlite & vermiculite?? I've seen perlite at Lowe's and such, and have heard of vermiculite, and wondered if they could be interchanged in your formula. Also, the CRF I plan on using is the MG Shake & Feed with Calcium. Would this be a good choice??

Okay,let's try this again... MG 3 bags @ 64 qts, 1 large bag vermiculite, about 40 quarts, have to find it again.., and the MG Shake N' Feed with Calcium Fertilizer. It's a 9-4-12 with 3.5% Ca. It also has 1.4% Mg.

Still trying to find the pine bark component. The only thing I have found so far is the huge chunk mulch, can't find the fines that you talk about.

Am I getting any closer???

Vermiculite and perlite are quite different in that vermiculite holds a LOT more water, something you wouldn't consider a plus in most container media because most are already too water-retentive to be ideal, even w/o the vermiculite. Vermiculite increases water retention on a per volume basis and perlite reduces it.

I wouldn't obsess over the bark, but I think it is worth looking for because in the right soil it has the potential to make a significant difference in your ability to bring along healthy productive plant material.

I have consistently had the best results with 3:1:2 ratio fertilizers. I use Foliage-Pro 9-3-6 for virtually everything I grow. Miracle-Gro 24-8-16 and 12-4-8 are the nearest equivalents. The 9-4-12 is ok if that's what you want to use, and it's an ok choice for tomatoes. If you're adding lime to your soil when you make it, the Ca & Mg in your fertilizer is just a duplication of what's already in the soil, and wouldn't offer anything in the way of potential to be a plus, not even as a guard against BER in all likelihood.

Al

Need 3/8" mesh hardware cloth -- can anybody provide a lead on where to buy? Nothing local, haven't found in searches online, etc. I have some extra 1/8" mesh if anyone wants to swap. TIA
Mary

Mary,
I never have found 3/8" and, since Al said getting pretty close was good enough, I screen through 1/2" mesh for my container mix.

Use 1/2" if you can't find 3/8"

Al

^^_^^!
Y P-B-Fs BFF!

I never found 3/8", except from specialty shops online that sell to industry.
Or MSC direct - way too expensive.

I let it roll quickly off 1/2" mesh so the smaller bits go through faster.

Then I use 1/4" mesh - very slowly - to get rid of as many fines as I have patience for.

Your Pine Bark Fines Best Friend Forever!

Y PBFs BFF!

I use everything that falls through the 1/2" mesh. Fines are important to my container recipe.

The larger, captured chunks will go into my raised bed, as is, to add bulk and structure. They'll eventually break down, but fresh large chunks will hold up the soil structure for aeration and drainage, and help retard compaction, at least for a couple seasons.

If I needed the larger chunks for more container mix, I'd run them through a chipper and sift again...

TX_gardener>> Thanks for the idea of the fry basket to use as a strainer. I've got one like that and I think it's a 3/8" mesh.. Let's hope, have to look in the workshop tomorrow and take a look for it. Even the 1/2" mesh isn't too cheep...

Some pictures of the components and results of making the container mix...

The chunks from 5 bags of mulch...

This message was edited Apr 23, 2012 10:30 PM

The finished container with a Sweet 100 Cherry plant...

A close-up of the inside of the container...

The mix up close...

A sifter & his helper...

All the containers on the new mulch bed...

Big double batch plus of the mix...

Kev,
Great job!

Now. Go find yourself some FREE buckets...LOL!!!
►pickle buckets at your local hamburger joint
►at your local bakery (the icing comes in 5-gallon buckets)
►from your friends who have cats (the large yelllow, square kitty litter buckets...)

Linda and her helper! ^^_^^^^_^^

Thanks for the local bakery tip. Lorelai's other grand mother works as a cake decorator at a big grocery store. I'm pretty sure she can get some buckets... I use the kitty litter buckets as project buckets when I do stuff around the house. I put all the odds & ends in them so I don't have to make 10 trips to the workshop cause I forgot something, didn't think about them for the garden.

What veggies would be good candidates for the "kitty litter" buckets??

Cabbages! Those yellow buckets come in two sizes, and the larger one is perfect for individual cabbages. They have just enough depth for the roots, and enough surface for a nice big cabbage to balance itself on.

Hugs!

I started the small, late cabbage transplants in those smaller ones because I didn't think they'd do anything so late. Fooled me!

But, you can also see how the bigger one would be better. The weight of a larger cabbage will tip the small bucket if it's not perfectly balanced!

>> It just seemed 1/2 was too large and 1/4 too small,

I agree with that

>> I use everything that falls through the 1/2" mesh. Fines are important to my container recipe.

One bag of pine bark mulch was too fine for that: it had a LOT that went easily through 1/4" mesh and has too soggy. But then, that year,m I also added a little of a peat-based potting mix and regretted it.

A different bag of mulch ("Medium Grade") had fewer fines, but still more than I wanted. So I used what went thorugh 1/2" screen FAST, and used a 1/4" screen to remove some of the fines from that.

Kevcarr: it looks like you hav e some slivers of white wood in your mix. Does that seem to give you any trouble?

I sifted 5 bags Saturday and there wasn't a LOT of difference except the end of the last bag it had a lot more chunks. The fibers didn't seem to be a big problem as most of them were less than 1/2" wide or thick & about 1" long. Even before I mixed everything, when you would grab a handful of the fines, the big pieces and fibers would rise to the top. I know this mix is very fast & I might add a little more peat component to slow it down just a little bit...

I was thinking I may have added a bit too much perlite into the mix, as you can see how white it looks. Will make a little test batch, a few containers worth just to see if it's any better. Got some red, yellow, and green Wonder peppers tonight, along with some Big Bertha's, and a couple Sun Sugar Tomato that need to go into containers tomorrow.

Never a dull moment....

Kev,
Just stick with the ratios, and the perlite will handle itself. It does rise to the top, though, so it looks like there's an abundance, but don't worry.

5 pts. PBFs
1 pt peat
1 pt perlite

and you're set!

My formula to slow it down some was:
4 pts. PBFs
2 pts peat
1 pt perlite

And, in some buckets I even went with:
3 pts. PBFs
2 pts peat
1 pt perlite

Just play around with it, until you get the moisture-holding action the plant likes best!

Only 1 of the Sweet 100's I transplanted in the 5 gallon buckets are doing good, the other 2 are very stressed indeed. Looks like the moisture is there, but I may have been over watering, not sure. Also lost 2 beans transplanted at the same time...

Added a little peat to the mix and have used it for some peppers and some Sun Sugar tomatoes, and they look to be doing a lot better... Getting ready to put some okra in the containers, and with 90+ highs and low 70's for the rest of the week, will just see what happens.

Finally found the lime at Lowe's and will be adding that into the mix... My other thought was the CFR was several years old and I wondered if that might enter into the equation...

How much fertilizer are you adding per eBucket? And, what kind (strength) of fert?

Bought some new Osmocote Indoor Outdoor Plant fertilizer with the 19-4-6, if I'm not mistaken, and added about a tablespoon per bucket and scratched it into the top. I've also noticed the buckets seem to be staying more moist these last few days. I think that may be because the bucket mix is finally getting fully wetted and the water is finally staying more toward the top of the bucket and around the root system...

When I started noticing this leaf problem I was still watering on a daily basis, but since have cut back. So far I've lost the Kentucky pole beans, which were in a bit smaller buckets, but these plants were only about 6" tall. Also lost the Beefsteaks that were sowed in an aluminum pan that Momma threw in there when she was planting. Those were transplanted into some peat pots after they actually germinated. I also had some that were germinated under lights and those were much thinner than the ones started in the garden.

Not ready to give up on the container mix, but not exactly working like I thought it would.

Do your buckets have reservoirs, and, if so, why are you watering every day? If you have reservoirs, you should only be watering through the fill tube, and just to the point that the water comes out of the overflow hole.

Or, are you growing in free-draining buckets with holes in the bottoms. That's a different story altogether...

LMK.

Linda

Free-draining buckets with about 5 or 6 7/8" holes... 1 in center, rest on perimeter on bottom... The pots the beans are in are about 4 gallon nursery pots. I didn't have the supply of 5 gallon buckets acquired at that time but had to get the beans out of the little peat pots, and then the weather cooled off. That's why I figured they were just kind of sulking...

Peppers are actually doing pretty good, and I have them in various sized pots to see how they react. Got some Big Bertha's and have them in a 5 gallon bucket. Woman at nursery said I could probably get away with putting 2 pepper plants in each bucket, what do you think??

Your potting mix should be staying moist enough for you to only need to water every two days. It will look much drier on the top than the moisture content deeper in the bucket. It took me quite awhile to accept that the top 1" or so could look bone dry, but there was actual moisture in the rest of the bucket. There was...

And, for future buckets, I might recommend more drainage holes on the bottoms, and some holes on the sides, about 1/4" up from the bottom, all the way around.

I've never grown more than 1 pepper per bucket, but you could try and see what happens. I'm thinking competition for leaf space and sun if they get too thick and bushy...?

Linda

When I pulled the dead bean & tomatoes out of the buckets I scooped down and found out how moist the mix was down deep. I guess I've way over-watering these pots and haven't for the last 3 days. Checking deeper today they are still moist down about 1 1/2", so I will start watering again tomorrow, and use less water. Since I haven't watered the borderline plants seem to be coming around. Maybe I can save a couple, but will reseed the beans again and give them another chance.